14
Displacement of test mass The horizontal isolation >3Hz is due to a heat link of 0.03Hz. The vertical isolation is better than the horizontal isolation around 1Hz because of 4 stage GAS filters. Since the final stage (TM) is suspended by 4 sapphire fibers of φ1.8mm, the vertical resonant frequency is about 100Hz. Heat links of 0.03Hz with 1% coupling from vertical mode satisfy demands at 10Hz.

15
Displacement of each system The isolation of Type-B is better than the isolation of Type-A with heat links >4Hz. When the part of IP-GASF of Type- B is fixed (iLCGT), the isolation of Type-A is worse than the isolation of Type-C with stack >20Hz.

17
SimMechanics (The MathWorks TM ) Based on multi body dynamics I)If geometric/topological parameters are determined, equations of motion/transfer functions are obtained almost automatically. II)Direct integration into the Simulink environment. III)How it is calculated is in a black box. Rigid Body Model by T. Sekiguchi

19
Octopus Octopus is a non-official Virgo tool. The modeling will be used for AdV, but it is not the only model that can be used. It provides (once completed): I) Point-by-point 6x6 matrixes of Force/displacement TFs or displacement ratios. II) Designing tool: several configurations or parameter tuning, within a given configuration can be explored. III) Some add-ons as fitting a dataset of experimental TF and extracting a fit which can be used to extract actual mechanical parameters (…). Rigid Body Model by E. Majorana

20
This presentation/practical cases. - Often it is useful to show longitudinal/pitch and transversal/yaw sub-matrixes - In the case of LCGT, the Vertical might be more crucial and should be included. Example of outputs of Octopus X Y Z Tx Ty Tz FxFx FyFy FzFz F tx F ty F tz